“Some sections of the community have expressed concern about whether the range of material included in the RC category currently reflects community standards”, Senator Conroy said.

His department is recommending an independent review of what the community deems to be inappropriate content. Senator Conroy expects the review to take around a year, and the filter will not be introduced during this time.

In the interim, several big ISPs including Telstra, Optus and Primus have agreed to voluntarily block a list of child porn and child abuse URLs provided by the government.

Maha Krishnapillai, Optus’ Director of Government and Corporate affairs, said he was very supportive of the measures.

“There have been a lot of misconceptions about what kind of things will be blocked, and that we are the ones who are blocking them”, he said.

“If people want to look at (content that’s currently rated RC), that’s ok, we don’t care. So if the review comes back and says that stuff’s ok it will be ok.”

In many European countries ISPs block content according to a voluntary code, without mandatory filtering or government involvement.

Mr Krishnapillai said he imagines a similar system will eventually be implemented in Australia.

“We have a long way to go before we get there. These are just the first steps.”

Blocking will be accomplished simply using a list of URLs known to contain RC content, meaning slow-down to internet speeds will not be noticeable.

When the filter is introduced, measures will come in alongside it including a notification to the owner of the page before it is blocked, an appeal and review mechanism, industry consultation on technical issues and the immediate classification of any pages that are complained about by public.

Attempting to access a blocked URL will display a page giving detailed information on why it was blocked, and the ACMA website will frequently update an exhaustive list of reasons why a website may be blocked.

Senator Conroy denied that these changes are being instituted as an election issue, though given his focus on clearing up ‘misconceptions’ about the filter, it seems likely the aim is to appease the voters.

He also said the filter is not designed as a “silver bullet” that will make accessing the internet safe, but it is a major part of a multi-million dollar plan that also includes education, training and increased online law enforcement.